Panduit MRT4H-L4 Pan-Steel 304 Stainless Steel Retained-Tension Cable Tie, 18.5 in, 50-Pack
Overview
The Panduit MRT4H-L4 is a 304 stainless steel retained-tension cable tie from the Panduit Pan-Steel line — built for wiring and bundling applications where vibration, heat, and corrosive environments would shorten the life of a nylon tie. At 18.5 inches long with a 4.0-inch maximum bundle diameter and a rated tensile strength of 1,780 lb, this tie handles substantial wiring harnesses, conduit bundles, tubing runs, and armored cable — not just light-duty wire management. The self-closing head design is the defining feature: it locks at any point along the strap, which meaningfully speeds up installation in tight spaces where finessing a standard ratchet head is frustrating. If you're routing wire bundles in a cable and wire management application that sees vibration, heat cycling, or outdoor exposure, the MRT4H-L4 belongs on your shortlist.
Key Features
- 304 Stainless Steel Construction: Type 304 stainless resists corrosion in outdoor, washdown, and high-humidity environments where nylon ties become brittle and fail over time. If your installation will see weather, chemical exposure, or elevated temperatures, 304 SS is the baseline material to specify — not a premium upgrade.
- Self-Closing Head — Locks at Any Position: The patented auto-locking head engages at any point along the strap, not just at predetermined notches. In practice this means one-handed installation is faster and you don't have to thread the tail through a tight ratchet mechanism in confined conduit trays or junction boxes.
- 1,780 lb Tensile Strength: That rating puts the MRT4H-L4 well into heavy-duty bundling territory. Armored cable runs, conduit bundles, and high-vibration machinery harnesses are appropriate applications. For lighter-duty wire management, a lower-rated tie saves cost — but for anything subject to mechanical stress or shock load, the 1,780 lb rating provides meaningful margin.
- 18.5-Inch Length, 4.0-Inch Max Bundle Diameter: The 18.5-inch strap accommodates bundles up to 4.0 inches in diameter, which covers most multi-cable runs encountered in security system raceways, industrial control panels, and HVAC or mechanical equipment rooms. Verify your bundle diameter before ordering — the 4.0-inch maximum is a hard ceiling, not a soft guideline.
- High-Vibration Retention: The retained-tension head design maintains clamp force under vibration — relevant on motor control panels, compressor rooms, or anywhere cable bundles are subject to continuous mechanical movement that gradually loosens conventional ties.
- Compatible with MTRTLS and PTRT Installation Tools: The MRT4H-L4 is designed to work with Panduit's MTRTLS and PTRT tensioning tools, which apply consistent, calibrated pull force and cut the tail flush. Tool-applied ties produce uniform tension across a bundle run — important when consistent clamp force matters for code compliance or cable manufacturer bend-radius requirements.
- 50-Piece Package (Carton Qty 250): The standard sell unit is 50 ties per pack, with cartons of 250 available for larger project volumes. For a Panduit cable ties project requiring consistent material across phases, ordering in carton quantities reduces per-unit cost and ensures lot consistency.
Integration and Compatibility
The MRT4H-L4 (often searched as MRT4H L4) is a general-application tie rated for use with shielded and armored cables, rubber sheaths, heat sleeves, tubing, pipe, and conduit. It is not category-specific — it will install anywhere a 304 stainless tie in this size range is appropriate. For tensioning and tail-cutting, pair it with compatible Panduit installation tools — specifically the MTRTLS or PTRT tools identified in the product data. Using a calibrated tensioning tool is especially important on high-vibration applications where under-tensioning or over-tensioning both create problems over time.
What's in the Box
- 50x Panduit MRT4H-L4 Pan-Steel 304 Stainless Steel Retained-Tension Cable Ties (18.5 in)
Frequently Asked Questions
Q: What is the maximum bundle diameter the MRT4H-L4 can accommodate?
A: The MRT4H-L4 handles bundles up to 4.0 inches in diameter. The strap is 18.5 inches long, and the 4.0-inch max bundle diameter is a hard specification — measure your bundle before ordering to confirm fit.
Q: What material is the MRT4H-L4 made from?
A: It is made from Type 304 stainless steel, which provides corrosion resistance for outdoor, high-humidity, washdown, and chemically exposed environments.
Q: What tensile strength is the MRT4H-L4 rated for?
A: The MRT4H-L4 is rated to 1,780 lb tensile strength, placing it in the heavy-duty category suitable for armored cable, conduit bundles, and high-vibration machinery harness applications.
Q: What installation tools are compatible with the MRT4H-L4?
A: Panduit specifies the MTRTLS and PTRT tensioning tools for use with the MRT4H-L4. These tools apply calibrated tension and cut the tail flush, ensuring consistent clamp force across a bundle run.
Q: How many ties come in a package, and are larger quantities available?
A: Each package contains 50 ties. Carton quantity is 250, making carton ordering practical for larger installations requiring consistent lot material.
Q: Is the MRT4H-L4 suitable for high-vibration environments?
A: Yes. The retained-tension head design is specifically engineered to maintain clamp force under vibration — a key reason to choose this model over a standard stainless steel cable tie on motor panels, compressor rooms, or equipment subject to continuous mechanical movement.
The MRT4H-L4 gets specified in situations where a standard nylon tie — or even a basic stainless wrap — just doesn't hold up. That 1,780 lb tensile rating combined with the retained-tension head is what separates this from commodity stainless ties: the head locks at any point along the strap, so you're not fighting a ratchet mechanism in a tight conduit tray, and once it's locked, vibration isn't going to walk it loose over a service cycle.
Technical Highlights:
- 304 Stainless Steel: Corrosion resistance that matters in outdoor enclosures, rooftop equipment, and washdown environments — where nylon ties fail within a season and basic zinc-coated hardware rusts within two years.
- 1,780 lb Tensile Rating: Substantial margin for armored cable bundles and multi-conduit runs. Most security and industrial installations won't come close to this limit, but the rating also tells you the head and strap geometry are engineered for mechanical stress — not just light bundling duty.
- 18.5 in / 4.0 in Max Diameter: Sized for real cable runs, not single-conductor wire dressing. A 4.0-inch bundle handles a meaningful multi-cable security riser or a conduit cluster on an outdoor equipment pad.
Deployment Considerations:
- The MTRTLS and PTRT tools are specified for this tie — hand-tensioning alone won't deliver consistent clamp force across a long run of ties. If you're doing a large install, budget for the tool; the per-tie consistency is worth it.
- At 4.0 inches max bundle diameter, this is not the right tie for very large conduit bundles or cable trays with dozens of conductors. Measure the bundle before specifying — there's no adjustment once the head locks.
The MRT4H-L4 is the right specification for security and AV infrastructure in mechanical spaces, rooftop equipment enclosures, and any installation where vibration or environmental exposure rules out nylon — particularly compressor rooms, rooftop camera mast wiring, and industrial control panel dressing where you need the tie to outlast the equipment it's securing.
